diff --git a/rewriter/.cargo/config.toml b/rewriter/.cargo/config.toml
new file mode 100644
index 0000000..da39be7
--- /dev/null
+++ b/rewriter/.cargo/config.toml
@@ -0,0 +1,4 @@
+[profile.release]
+opt-level = "z"
+lto = true
+codegen-units = 1
diff --git a/rewriter/build.sh b/rewriter/build.sh
index 0f13bad..e73e924 100644
--- a/rewriter/build.sh
+++ b/rewriter/build.sh
@@ -1,4 +1,4 @@
-RUSTFLAGS='-C target-feature=+atomics,+bulk-memory' cargo build --lib --target wasm32-unknown-unknown -Z build-std=panic_abort,std --release
+RUSTFLAGS='-C target-feature=+atomics,+bulk-memory -Zlocation-detail=none' cargo build --lib --target wasm32-unknown-unknown -Z build-std=panic_abort,std -Z build-std-features=panic_immediate_abort,optimize_for_size --release
 wasm-bindgen --weak-refs --target web --out-dir out/ target/wasm32-unknown-unknown/release/rewriter.wasm
 
 sed -i 's/import.meta.url/""/g' out/rewriter.js
@@ -7,7 +7,7 @@ cd ..
 
 WASM=rewriter/out/rewriter_bg.wasm
 
-time wasm-opt -O4 --vacuum --dce --enable-threads --enable-bulk-memory --enable-simd "$WASM" -o rewriter/out/optimized.wasm
+time wasm-opt -Oz --vacuum --dce --enable-threads --enable-bulk-memory --enable-simd "$WASM" -o rewriter/out/optimized.wasm
 # cp "$WASM" rewriter/out/optimized.wasm
 
 echo -n "self.WASM = '" > static/wasm.js